首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   4572篇
  免费   242篇
  国内免费   2篇
  2023年   39篇
  2022年   34篇
  2021年   71篇
  2020年   109篇
  2019年   126篇
  2018年   144篇
  2017年   170篇
  2016年   165篇
  2015年   117篇
  2014年   165篇
  2013年   558篇
  2012年   228篇
  2011年   238篇
  2010年   146篇
  2009年   156篇
  2008年   205篇
  2007年   219篇
  2006年   213篇
  2005年   159篇
  2004年   135篇
  2003年   136篇
  2002年   148篇
  2001年   75篇
  2000年   79篇
  1999年   55篇
  1998年   58篇
  1997年   53篇
  1996年   46篇
  1995年   39篇
  1994年   36篇
  1993年   38篇
  1992年   49篇
  1991年   30篇
  1990年   27篇
  1989年   36篇
  1988年   23篇
  1986年   28篇
  1985年   31篇
  1984年   22篇
  1983年   23篇
  1982年   27篇
  1981年   32篇
  1980年   17篇
  1978年   22篇
  1977年   25篇
  1976年   26篇
  1975年   22篇
  1974年   21篇
  1973年   21篇
  1971年   19篇
排序方式: 共有4816条查询结果,搜索用时 7 毫秒
101.
Four experiments examined the conceptual organization of narrative passages and the extent to which these representations were explanatory in a variety of experimental tasks. The conceptual representation of a passage consisted of a graph of labeled nodes and labeled, directed arcs which were adopted from the Conceptual Dependency Theory. These representations included both explicitly stated information and inferences which had been empirically extracted by a question-answering procedure. Symbolic procedures for answering how- and why-questions were also delineated. The conceptual representations and the symbolic procedures that operate on these representations together accounted for 91% of the answers generated from question-answering protocols in Experiment 1, and also the rated quality of specific answers to specific questions in Experiment 2. Experiments 3 and 4 supported the hypothesis that structural properties of the representations can predict recall of explicitly stated nodes and verification ratings of inference nodes. The results provide encouraging support for the proposed graphic representations and also for the use of question-answering protocols in uncovering prose inferences.  相似文献   
102.
This study of kindergarten-aged hyperactive children evaluated the effects of three modes of treatment in relation to an untreated control group. The treatments were administered over a 3-month period and included cognitive behavior modification, methylphenidate, and the two treatments combined. A follow-up assessment was done approximately 1 year later at the end of the first grade. Analyses of psychological, rating scale observational, and interview data showed that hyperactive children became less symptomatic over time;the data did not provide evidence indicating that any of the treatments studied was more effective than any other or than no treatment at all.This research was supported by grants from the Ontario Mental Health Foundation (Grant No. 701-76/78) and The Hospital for Sick Children Foundation (Grant No. 77-22). The authors wish to thank Mr. Syl Sauro, of the Etobicoke Board of Education, and Mrs. M. Stijovic, of the Etobicoke Community Health Department, for their cooperation.  相似文献   
103.
Native Israeli readers read Hebrew and English text as their eye movements were monitored. A window of text moved in synchrony with their eye movements and the window was either symmetrical about the fixation point or offset to the left or right. When subjects were reading Hebrew, the perceptual span was asymmetric to the left and when they were reading English it was asymmetric to the right. The results point out the importance of attentional factors in reading.  相似文献   
104.
105.
Four experiments investigated the effects of a priming food reinforcement, given 0 or 75 sec pretrial, on runway performance of rats. The studies differed in the use of between-versus-within-subject designs, and by using food or water as the goal reinforcer. In Experiment 1, using food as the goal reward, subjects primed with food 0 sec pretrial conditioned slower than subjects primed 75 sec pretrial. In Experiment 2, using water as the goal reward, subjects primed with food 0 sec pretrial conditioned faster. These differences were evident on both prefed trials and on nonprefed test trials. Experiments 3 and 4 showed an opposite pattern of results when within-subject comparisons of 0- and 75-sec pretrial intervals were used: Food priming immediately pretrial facilitated food-rewarded running but inhibited water-rewarded running. The results suggest prefeeding has differential effects on acquisition and performance of instrumental behavior, and also depending upon the similarity of the priming and goal reinforcers.  相似文献   
106.
After subjects established fixation on a target cross, 12 dots were presented parafoveally. When the dots were presented, the subjects made an eye movement to the location of the dots, and during the saccade the 12 initially presented dots were replaced by 12 other dots. The 24 dots were part of a 5 × 5 matrix, and the task of the subject was to report which dot was missing. The data were consistent with other recent studies: subjects could successfully report the location of the missing dot far above chance (54%), whereas performance in a control condition (in which the two sets of dots were presented to different spatial and retinal locations) was almost at chance level (10%). However, a number of control conditions demonstrated that the effect was due primarily to persistence from the phosphor of the cathode ray tube used for stimulus presentation and that little of the visual information integrated was across two fixations. Implications of the results for a theory of integration across saccades are discussed.  相似文献   
107.
108.
Although the FACES has become a widely used instrument for assessing children's family relations, the possible linearity vs. curvilinearity of its cohesion and adaptability scales has been treated inconsistently by investigators. This study evaluated whether samples of adolescent repeat offenders, young adult prisoners, and adolescent nonoffenders were discriminated better by a linear or curvilinear treatment of the FACES scores. Between-groups comparisons showed that significant effects were observed for each of the three curvilinear measures (cohesion-curvilinear, adaptability-curvilinear, distance-from-center) and only one of the two linear measures (cohesionlinear). These findings support the superiority of a curvilinear treatment of the FACES. In light of these findings, it is suggested that investigators who use FACES evaluate the linearity of the scales and determine whether a linear or curvilinear treatment of the data produces more meaningful results.  相似文献   
109.
A preliminary electroencephalographic (EEG) investigation was conducted to determine if the pattern of hemispheric activation in mathematically precocious youth differs from that of average math ability subjects. Alpha activity at four brain sites (frontal, temporal, parietal, and occipital lobes) over the left and right cerebral hemispheres (LH/RH) was monitored while 12- to 14-year-old, right-handed males: (a) looked at a blank slide (baseline condition), (b) judged which of two chimeric faces was "happier," and (c) determined if a word was a noun or a verb. At baseline, the LH of the precocious group was found to be more active at all four brain sites relative to that of the average ability group. During chimeric face processing, the gifted subjects exhibited a significant reduction in alpha power over the RH, primarily at the temporal lobe, while no such alpha suppression was observed in the average ability subjects. For noun/verb determinations, no significant alpha power reductions were obtained for either group. These electrophysiological data generally corroborate the behavioral findings of O'Boyle and Benbow (1990a) and support their contention that enhanced RH involvement during cognitive processing may be a correlate of mathematical precocity. Moreover, the pattern of activation observed across tasks suggests that the ability to effectively coordinate LH and RH processing resources at an early age may be linked to intellectual giftedness.  相似文献   
110.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号